The present invention relates to a translation and locking mechanism for a projectile that is lying in a standby position within a rocket motor in a missile, where the projectile is translated in respect of the rocket motor by means of a pyrotechnic charge before the rocket motor is initiated,
The translation and locking mechanism according to the invention is developed for use in missiles, and in particular, but not exclusively, in rocket accelerated penetrators. Rocket accelerated penetrators are often kept in their storing and standby state with the main parts thereof not assembled. This means the part having control fins, the fin cone, and the rocket motor proper is assembled to the penetrator at the moment before the missile is launched from the launcher. The penetrator, which is in form of an arrow like body having substantial mass, is lying in standby position in a translation tube within the rocket motor and with the pointed end thereof supported in the control fin part. How the assembly operation happens is described in detail in the U.S. patent application no. 09/980,948.
During launching preparations the penetrator is translated through the translation tube and the control fin part and the rear end of the penetrator is interlocked to the control fin part immediately before the rocket motor is ignited. It is common practise that the rocket motor is separated from the penetrator during the flight thereof as soon as the rocket motor is burned out and has lost its propelling force. It is the mechanism for the translation of the penetrator, and more generally the projectile, and locking of the rear end of the projectile to the rocket motor the present application deals with.
According to the invention, a translation and locking mechanism of the introductorily described kind is provided, which is distinguished in that the rear and of the projectile and the front and of the rocket motor comprises respectively either at least one radially spring biased locking means or a circumferential groove that the at least one locking means snaps into when the at lent one locking means and the groove are aligned.
In a first alternative embodiment, it is the rear end of the projectile tat includes the at least one radially spring biased locking means and it is the front part of the rocket motor. that includes the circumferential groove that the at least one locking means snaps into when the at least one locking means is translated to and is aligned with the groove, which at least one locking means is spring biased radially outwards and the groove is an internal circumferential groove in the front part of the rocket motor.
In a second embodiment, it is the front part of the rocket motor that includes the at least one radially spring biased locking means and it is the rear end of the projectile that includes the circumferential groove that the at least one locking means snaps into when the groove is translated to and is aligned with the at least one locking means, which at least one locking means is spring biased radially inwards and the groove is an external circumferential groove in the rear part of the projectile.
In one embodiment, the rear part of the projectile can be an integrated power piston that follows the projectile during the flight thereof.
In a second embodiment, the power piston can be releaseable from the projectile together with the rocket motor.
As one among several alternatives, each locking means can be in form of a locking lug, or retainer, that tends to radial outwards directed motion by means of a spring which is located underneath the retainer. The configuration of the retainer and the number thereof can vary according to desire.
The locking means can, as one of the alternatives, be like a C-formed locking ring of the xe2x80x9cpiston ring typexe2x80x9d and is then one single part that has both the inherent spring bias outwards and have the same locking function as a retainer in the groove.
It is to be understood that the translation and locking mechanism has performed the mission thereof before the rocket motor is initiated and launched.